The invention set forth in this specification pertains to new and improved pipe holders. More specifically it pertains to pipe holders corresponding to prior or known pipe holders but differing from such prior or known pipe holders as a result of having been modified so as to use substantially triangular pipe supporting fins constructed as subsequently described. Such fins are employed to engage and support pipes or tubes so that such pipes or tubes are not apt to become damaged and in such a manner so as to minimize sound and heat transmission from such pipes and to avoid such pipes being electrolytically attacked.
The prior or known holders mentioned in the preceding paragraph can be constructed in many different manners. Because of this it is considered impractical to try and set forth in this specification all of the various holders which can be modified in accordance with the concepts of the invention. The holders which can be constructed so as to use the concepts of the invention will normally be comparatively simple holders designed to have substantially cylindrical internal surfaces designed to be opposed to the external surfaces of pipe so as to support such pipe.
It is believed that the present invention will be most beneficial when used with comparatively uncomplex pipe holders or clamps constructed as one piece integral units out of a polymer material or composition having a moderate degree of resiliency and flexibility such as is possessed by common grades of polyethylene, polypropylene, various common plasticized vinyl compositions and the like as are currently employed in the manufacture of holders and claims which are reasonably related to those described in this specification.. At the present time there are many known polymers possessing these physical properties. Many of them are blends of known polymer materials.
Normally such holders or camps will be formed so as to include a plurality of spaced internal "Vee" shaped or more or less arrow head shaped ridges extending radially inwardly from the cylindrical surfaces in such a manner that the pointed ends of the these ridges engage the pipes held by such holders at at least three different locations around the peripheries of such pipes in order to firms support such pipes. In order to achieve such a supporting action the ridges usually extend parallel to the axes of the cylindrical surfaces and are located so that when a pipe is in position in such a holder they are closer to the axis of the cylindrical surface than the periphery of the pipe. As a consequence of this any pipe held in such a holder is held under compression as a result of a limited amount of material deformation in connection with the ridges and/or the body of the older adjacent to the surface upon which the ridges are located.
This can be easily comprehended by a consideration of clamps or holders such as are disclosed inthe U.S. Pat. Nos. 3,684,223 and 3,684,220. Although the clamps or holders disclosed in these patents are effective, desirable devices their desirability is somewhat limited by virtue of the fact that as they are used the pointed ridges or fins disclosed in them will frequently tend to apply pressure directly toward the axis of a pipe more or less like a point of an arrow will tend to apply pressure to the skin on a finger as it is pressed towards the finger. Although this is not often serious in some circumstances it can be significant. The latter is particularly the case when the pipe supported has a comparatively thin periphery wall.
This situation is particularly of concern when the pipe is a comparatively thin walled tube which can be easily distended or cracked when held under pressure. On occasion such tube are formed of materials which are prone to "stress cracking". This means that they will tend to crack open when held under significant compression or tension for a prolonged period. It is believed that such stress cracking of many common types of tubes is particularly significant when they are held under compression for a prolonged period against comparatively sharp ridges or fins as are disclosed in the patents mentioned in the preceding. It is also believed that such stress cracking of pipes or tubes is particularly significant in connection with comparatively thin walled tubes of thermoplastic materials, especially when such tubes are used with comparatively hot fluids or in a comparatively hot environment.